Mercurial > sdl-ios-xcode
annotate src/audio/SDL_mixer.c @ 1312:c9b51268668f
Updated copyright information and removed rcs id lines (problematic in branch merges)
I batch edited these files, so please let me know if I've accidentally removed anybody's
credit here.
author | Sam Lantinga <slouken@libsdl.org> |
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date | Wed, 01 Feb 2006 06:32:25 +0000 |
parents | b8d311d90021 |
children | 450721ad5436 |
rev | line source |
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0 | 1 /* |
2 SDL - Simple DirectMedia Layer | |
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3 Copyright (C) 1997-2006 Sam Lantinga |
0 | 4 |
5 This library is free software; you can redistribute it and/or | |
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6 modify it under the terms of the GNU Lesser General Public |
0 | 7 License as published by the Free Software Foundation; either |
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8 version 2.1 of the License, or (at your option) any later version. |
0 | 9 |
10 This library is distributed in the hope that it will be useful, | |
11 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
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13 Lesser General Public License for more details. |
0 | 14 |
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15 You should have received a copy of the GNU Lesser General Public |
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16 License along with this library; if not, write to the Free Software |
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17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
0 | 18 |
19 Sam Lantinga | |
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20 slouken@libsdl.org |
0 | 21 */ |
22 | |
23 /* This provides the default mixing callback for the SDL audio routines */ | |
24 | |
25 #include <stdio.h> | |
26 #include <stdlib.h> | |
27 #include <string.h> | |
28 | |
29 #include "SDL_audio.h" | |
30 #include "SDL_mutex.h" | |
31 #include "SDL_timer.h" | |
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32 #include "SDL_cpuinfo.h" |
0 | 33 #include "SDL_sysaudio.h" |
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34 #include "SDL_cpuinfo.h" |
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35 #include "SDL_mixer_MMX.h" |
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36 #include "SDL_mixer_MMX_VC.h" |
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37 #include "SDL_mixer_m68k.h" |
0 | 38 |
39 /* This table is used to add two sound values together and pin | |
40 * the value to avoid overflow. (used with permission from ARDI) | |
41 * Changed to use 0xFE instead of 0xFF for better sound quality. | |
42 */ | |
43 static const Uint8 mix8[] = | |
44 { | |
45 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
46 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
47 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
48 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
49 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
50 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
51 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
52 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
53 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
54 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
55 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
56 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x02, 0x03, | |
57 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, | |
58 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, | |
59 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22, 0x23, 0x24, | |
60 0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, | |
61 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, | |
62 0x3B, 0x3C, 0x3D, 0x3E, 0x3F, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, | |
63 0x46, 0x47, 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, 0x50, | |
64 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x5B, | |
65 0x5C, 0x5D, 0x5E, 0x5F, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, | |
66 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70, 0x71, | |
67 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x7B, 0x7C, | |
68 0x7D, 0x7E, 0x7F, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, | |
69 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E, 0x8F, 0x90, 0x91, 0x92, | |
70 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D, | |
71 0x9E, 0x9F, 0xA0, 0xA1, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, | |
72 0xA9, 0xAA, 0xAB, 0xAC, 0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, | |
73 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB, 0xBC, 0xBD, 0xBE, | |
74 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, | |
75 0xCA, 0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, | |
76 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, | |
77 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9, 0xEA, | |
78 0xEB, 0xEC, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, | |
79 0xF6, 0xF7, 0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFE, 0xFE, | |
80 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
81 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
82 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
83 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
84 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
85 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
86 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
87 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
88 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
89 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
90 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
91 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE | |
92 }; | |
93 | |
94 /* The volume ranges from 0 - 128 */ | |
95 #define ADJUST_VOLUME(s, v) (s = (s*v)/SDL_MIX_MAXVOLUME) | |
96 #define ADJUST_VOLUME_U8(s, v) (s = (((s-128)*v)/SDL_MIX_MAXVOLUME)+128) | |
97 | |
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98 void SDL_MixAudio (Uint8 *dst, const Uint8 *src, Uint32 len, int volume) |
0 | 99 { |
100 Uint16 format; | |
101 | |
102 if ( volume == 0 ) { | |
103 return; | |
104 } | |
105 /* Mix the user-level audio format */ | |
106 if ( current_audio ) { | |
107 if ( current_audio->convert.needed ) { | |
108 format = current_audio->convert.src_format; | |
109 } else { | |
110 format = current_audio->spec.format; | |
111 } | |
112 } else { | |
113 /* HACK HACK HACK */ | |
114 format = AUDIO_S16; | |
115 } | |
116 switch (format) { | |
117 | |
118 case AUDIO_U8: { | |
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119 #if defined(__M68000__) && defined(__GNUC__) |
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120 SDL_MixAudio_m68k_U8((char*)dst,(char*)src,(unsigned long)len,(long)volume,(char *)mix8); |
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121 #else |
0 | 122 Uint8 src_sample; |
123 | |
124 while ( len-- ) { | |
125 src_sample = *src; | |
126 ADJUST_VOLUME_U8(src_sample, volume); | |
127 *dst = mix8[*dst+src_sample]; | |
128 ++dst; | |
129 ++src; | |
130 } | |
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131 #endif |
0 | 132 } |
133 break; | |
134 | |
135 case AUDIO_S8: { | |
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136 #if defined(i386) && defined(__GNUC__) && defined(USE_ASMBLIT) |
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137 if (SDL_HasMMX()) |
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138 { |
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139 SDL_MixAudio_MMX_S8((char*)dst,(char*)src,(unsigned int)len,(int)volume); |
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140 } |
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141 else |
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142 #endif |
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143 #if defined(USE_ASM_MIXER_VC) |
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144 if (SDL_HasMMX()) |
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145 { |
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146 SDL_MixAudio_MMX_S8_VC((char*)dst,(char*)src,(unsigned int)len,(int)volume); |
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147 } |
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148 else |
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149 #endif |
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150 #if defined(__M68000__) && defined(__GNUC__) |
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151 SDL_MixAudio_m68k_S8((char*)dst,(char*)src,(unsigned long)len,(long)volume); |
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152 #else |
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153 { |
0 | 154 Sint8 *dst8, *src8; |
155 Sint8 src_sample; | |
156 int dst_sample; | |
157 const int max_audioval = ((1<<(8-1))-1); | |
158 const int min_audioval = -(1<<(8-1)); | |
159 | |
160 src8 = (Sint8 *)src; | |
161 dst8 = (Sint8 *)dst; | |
162 while ( len-- ) { | |
163 src_sample = *src8; | |
164 ADJUST_VOLUME(src_sample, volume); | |
165 dst_sample = *dst8 + src_sample; | |
166 if ( dst_sample > max_audioval ) { | |
167 *dst8 = max_audioval; | |
168 } else | |
169 if ( dst_sample < min_audioval ) { | |
170 *dst8 = min_audioval; | |
171 } else { | |
172 *dst8 = dst_sample; | |
173 } | |
174 ++dst8; | |
175 ++src8; | |
176 } | |
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177 } |
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178 #endif |
0 | 179 } |
180 break; | |
181 | |
182 case AUDIO_S16LSB: { | |
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183 #if defined(i386) && defined(__GNUC__) && defined(USE_ASMBLIT) |
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184 if (SDL_HasMMX()) |
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185 { |
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186 SDL_MixAudio_MMX_S16((char*)dst,(char*)src,(unsigned int)len,(int)volume); |
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187 } |
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188 else |
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189 #elif defined(USE_ASM_MIXER_VC) |
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190 if (SDL_HasMMX()) |
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191 { |
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192 SDL_MixAudio_MMX_S16_VC((char*)dst,(char*)src,(unsigned int)len,(int)volume); |
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193 } |
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194 else |
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195 #endif |
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196 #if defined(__M68000__) && defined(__GNUC__) |
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197 SDL_MixAudio_m68k_S16LSB((short*)dst,(short*)src,(unsigned long)len,(long)volume); |
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198 #else |
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199 { |
0 | 200 Sint16 src1, src2; |
201 int dst_sample; | |
202 const int max_audioval = ((1<<(16-1))-1); | |
203 const int min_audioval = -(1<<(16-1)); | |
204 | |
205 len /= 2; | |
206 while ( len-- ) { | |
207 src1 = ((src[1])<<8|src[0]); | |
208 ADJUST_VOLUME(src1, volume); | |
209 src2 = ((dst[1])<<8|dst[0]); | |
210 src += 2; | |
211 dst_sample = src1+src2; | |
212 if ( dst_sample > max_audioval ) { | |
213 dst_sample = max_audioval; | |
214 } else | |
215 if ( dst_sample < min_audioval ) { | |
216 dst_sample = min_audioval; | |
217 } | |
218 dst[0] = dst_sample&0xFF; | |
219 dst_sample >>= 8; | |
220 dst[1] = dst_sample&0xFF; | |
221 dst += 2; | |
222 } | |
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223 } |
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224 #endif |
0 | 225 } |
226 break; | |
227 | |
228 case AUDIO_S16MSB: { | |
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229 #if defined(__M68000__) && defined(__GNUC__) |
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230 SDL_MixAudio_m68k_S16MSB((short*)dst,(short*)src,(unsigned long)len,(long)volume); |
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231 #else |
0 | 232 Sint16 src1, src2; |
233 int dst_sample; | |
234 const int max_audioval = ((1<<(16-1))-1); | |
235 const int min_audioval = -(1<<(16-1)); | |
236 | |
237 len /= 2; | |
238 while ( len-- ) { | |
239 src1 = ((src[0])<<8|src[1]); | |
240 ADJUST_VOLUME(src1, volume); | |
241 src2 = ((dst[0])<<8|dst[1]); | |
242 src += 2; | |
243 dst_sample = src1+src2; | |
244 if ( dst_sample > max_audioval ) { | |
245 dst_sample = max_audioval; | |
246 } else | |
247 if ( dst_sample < min_audioval ) { | |
248 dst_sample = min_audioval; | |
249 } | |
250 dst[1] = dst_sample&0xFF; | |
251 dst_sample >>= 8; | |
252 dst[0] = dst_sample&0xFF; | |
253 dst += 2; | |
254 } | |
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255 #endif |
0 | 256 } |
257 break; | |
258 | |
259 default: /* If this happens... FIXME! */ | |
260 SDL_SetError("SDL_MixAudio(): unknown audio format"); | |
261 return; | |
262 } | |
263 } | |
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264 |